In some cases, importing a pre-made layout or a custom layout might get stuck at 1%. While this is unfortunate, there are a few reasons why that might happen:
The value of the upload_max_filesize PHP directive is less than the imported file size.
A firewall might prevent the importing process.
Other server-related issues.
Ensure that the upload_max_filesize size is sufficient
Ensure the PHP directive upload_max_filesize is set to at least 64M.
Go to WordPress Dashboard → Divi → Support Center → System Status.
Check if everything is in green, especially the upload_max_filesize.
Ensure that the memory_limit and max_execution_time also have at least the recommended values.
Firewall protection
Sometimes, the Server's Firewall or a plugin's Firewall might prevent the importing process from working correctly.
WordFence plugin
Go to WordPress Dashboard → WordFence → Firewall → Manage WAF.
Set Learning Mode for Web Application Firewall Status.
Leave the Learning mode set for at least 48 hours. After that, set it back to Enabled and Protecting.
Server's Firewall
Some hosting companies use their own internal Firewalls. Check with your hosting support team for more details about the server's configuration and try disaling the firewall temporarily to see if it works after that.
Other server-related errors
Enabling WordPress Debug mode can help identify errors that prevent importing functionality.
Enable the WordPress debug mode.
Try again to import the same layout.
Check the WordPress debug.log file in Divi → Support Center in the Logs section at the bottom and see if you get any fatal errors during your import process.